Method of and apparatus for purifying dairy products



06L 1938- c. DOERING ET AL 2,132,099

METHOD OF AND APPARATUS FOR PURIFYING DAIRY PRODUCTS Fil'ed Aug. 23,1934 5 Sheets-Sheet 1 A j ilorigz.

Oct. 4, 1938.

C. DOERING ET AL METHOD OF AND APPARATUS FOR PURIFYING DAIRY PRODUCTS 5Sheets-Sheet 2 Filed Aug. 25, 1934 Oct. 4, 1938. c. DOERING ET AL METHODOF AND APPARATUS FOR PURIFYING DAIRY PRODUCTS Filed Aug. 2:5, 1954 5Sheets-Sheet 5 lllll.

Oct. 4, 1938. c. DOERING El AL METHOD OF AND APPARATUS FOR PURIFYINGDAIRY PRODUCTS 5 Sheets-Sheet 4 Filed Aug. 25, 1934 Oct. 4, 1938. c.DOERING El AL METHOD OF AND APPARATUS FOR PURIFYING DAIRY PRODUCTS FiledAug. 23, 1934 5 Sheets-Sheet 5 Patented Oct. 4, 1938 PATENT OFFICEMETHOD OF AND APPARATUS FOR PURIFY- ING DAIRY PRODUCTS Charles Doeringand Henry Doering, Chicago, Ill.

Application August 23, 1934, Serial No. 741,103

4 Claims.

This invention relates to purifying devices and more particularly tomachines for. removing foreign matter from edible substances such ascream and similar dairy products preparatory to the processing thereof,although it may be employed with equal advantage for other pur-. poses.I

It contemplates more especially the provision of means for extractingthe impurities and forelgn matters from substances without resort topressure sieves and similar expedients heretofore employed for thatpurpose, thereby insuring utmost sanitation, continuous operation andimprovement in the qualities of such products.

Dairy products such as cream, butter and kindred edible foodscustomarily contain comparatively large quantities of foreign substancesbesides the usual micro-organisms that are eliminated or at leastrendered inactive by pasteurization. Pasteurization tends to preclude orat least retard deterioration occasioned by bacteria infestationresponsive to natural bacteria decay over an extended period of time,but dairy products like cream contain many additional foreign substanceswhich are inherent therein or are intermixed therewith during thehandling thereof and exposure to the atmosphere environs that areanything but sterile or clean. Fundamental ly, the difficulty ofcleansing cream or other dairy products with a pressure sieve or otherknown expedients is the inability to prevent the foreign constituentsfrom being passed therethrough with the liquid to be cleansed, for thedairy products like cream consist of fat globules having a strongaffinity for all foreign substances such as slime, insect bodies, anteggs, nucro-organisms, dirt from the atmosphere or included therein byhand contact in cow' milking, and such other undesirable matter that isusually prevalent around farms, pasteurizing equipment, dairies and thecreameries. There has been the practice, therefore, of employingpressure sieves and strainers after heat pasteurization in an attempt toremove these foreign substances, but such expedients requireintermittent replacements and the foreign substances for the most partpass through with the fat globules so that this is not productive ofuniformity or any appreciable purification. Then, too, the incorporationof chemicals is quite essential with customary processes of attemptedpurification, but this is accomplished at the expense of adulteration,which for the most part is prohibited by the pure food laws.

As a consequence the known devices for eifecting purification whichrequire the subjection of the dairy products to crude methods ofstraining and pressure expedients have not acquired perfection from boththe standpoint of continuous production and cleanliness in the resultingproduct. The present invention departs entirely from known processes inthat the fat globules comprising the cream or other dairy products arebroken up into a vast number of minute particles incident to processingto insure the separation of the foreign substances therefrom and impartincreased smoothness thereto. responsive to the purification thereofwithout resort to adulterants such as chemicals or pressure strainers.Moreover, edible dairy products are rendered more stable and improved intexture, color and odor by the subjection thereof to purification in amanner prescribed by the teachings of the instant invention, which isproductive of a decidedly superior product from a sanitary and tastestandpoint.

Dairy products are especially appetizing when possessed of a fineconsistency and purified to a degree that enables the decidedly improvedtaste owing to the purity and more or less emulsified condition thereofwhich results from processing in accordance with the teachings of thepresent invention. The keeping qualities and texture thereof areenhanced even more by resort to primarily mechanical rather than thermalprocessing to impart utmost purity and an accentuated homogenousconsistency with better keeping qualities to the natural dairy product.Improved texture with enhanced taste characteristics and purity areacquired without interfering with continuous production operations andundesirable pressure and/or crude strainers have been dispensed with.Thus, a completely pure and pasteurized product is produced without theslightest adulteration or processing impairment in that such is effectedin continuous sequence with the steps of initialp asteurizationsubsequent purification treatment.

One object of the present invention is the provision of means forpasteurizing and emulsifying dairy products and effecting thepurification" thereof to insure complete homogeneity, purity and animproved product.

Another object is to provide means for. continuously affecting thepasteurizationand purification of dairy products without resort topressure strainers.

Still another object is the provision of means, for improving dairyproducts by thorough mechanical rather than chemical purificationthereof.

A further object isthe provision of means for more satisfactorilypasteurizing and purifiying edible plastics by the subjection thereof toimproved mechanical expedients for accomplish ing that purpose.

A still further object is to provide novel mechanical means forpurifying edible dairy prod-; ucts to improve the texture and, tastequalities thereof.

Still a further object is the provision of a novel combination ofelements for mechanically purifying edible liquid substances resultingin a superior product havin improved keeping qualities, improved taste,better desirable color than in its initial or natural state.

An additional object is to provide means for breaking down theconstituents of liquid dairy products into particles more minute thanthe foreign substances therein contained and then removing the foreignsubstances without resort to pressure filters or strainers.

Other objects and'advantages will appear from the following descriptionof an illustrated embodiment of the present invention.

In the drawings:

Figure 1 is a side view in elevation of a device embodying features ofthe present invention, parts thereof being broken away to clarify theshowing.

Figure 2 is a front view in elevation of the device shown in Figure 1with a section taken substantially along line II-II thereof, there beingparts broken away to clarify the showing. Figure 3 is a sectional viewtaken substantially along line I1I-III of Figure2.

' Figure 4 is a plan view of the machine shown in Figures 1 and 2.

Figure 5 is a sectional view of the feeding device taken substantiallyalong line V-V of Figure 2.

Figure 6 is a sectional view taken substantially along the irregular oroffset line VI-VI of Figure 5.

Figure 7 is a front view of a rotor member taken substantially alongline VII-VII of Figure 1.

Figure 8 is an enlarged fragmentary 'view of a modified strainersupport, parts thereof being broken away to clarify the showing.

Figure 9 is a sectional view of the strainer support taken substantiallyalong line IX-IX of Figure 8.

Figure 10 is a sectional view taken substantially along line x-x ofFigure 8.

, Figure 11 is a sectional view in elevation of a strainer cleanser foruse in connection with the strainers shown herein.

Figure 12 is a fragmentary view in elevation of a modified embodiment ofthe present invention, parts thereof being broken away and certainothers shown in section to clarify the showing.

Figure 13 is a sectional view taken substantially along line XIII-XIIIofFigure 12.

Figure 14 is a perspective view of the strainer r embodying features ofthe present invention and utilized in conjunction with the device shownin Figures 1, 2 and 12.

Figure 15 is a sectional view taken substantially along line XV-XV ofFigure 14.

The structure selected for illustration comprises a standard In of anysuitable construction which extends vertically from the floor or otherfoundation to terminate in an enlarged flange ll stabilized by a base I2or as commercial practice may dictate. A frame I2 is fitted forattachment to the flange ll of the standard Ill to provide a rigid andnon-vibrating support for instrumentalities to be hereinafter described.To this end, the frame l2 has a pair of upstanding brackets I 3 and Ilwhich serve to support bearing members I! and I3, respectively, therebysustaining horizontally aligned bearings with auxiliaryinittrumentalities as will appear more fully herein ter.

As shown, liquid treating housing It hasa feedtexture and a more ingconduit I1 which extends in a vertically upward direction forcommunication with the inreceptacle I3 is mounted thereabove by means ofbrackets l3 and a coupler which is in threaded engagement with theconduit l1, the bracket ll depending to a motor housing 2| to eflect therigid horizontal support thereof. A suitable opening corresponding indimensional extent and contour to the interior of the feeding conduit 11is provided in the bottom 22 of the receptacle 1. for communicationtherewith so that a large volume of the liquid or .other substance to beprocessed and purified may conveniently and readily be supplied to thetreatment housing It for traverse and feeding along a predetermined pathin a manner and for a purpose that will appear more clearly hereinafter.

The treatment housing IC has, in this instance, a tubular entrantpassage 23 provided in a member 24 which provides a horizontallyextending stub shaft 25 having an extension 26 with an externallythreaded sleeve 21 fixed thereon. The bearing I5, is internally threadedto engage the sleeve 21, thereby supporting the front end of the housing16 and the receptacle IS. A frustoconical body or rotor member 23 isfixed to the extremity 29 of a shaft 30 fitted with spaced bearings 3|and 32 for Journalled support in a cylindrical member 33. Thecylindrical member 33 has an enlarged peripheral flange 34 whichconfronts the peripheral edge 35 of the liquid treatment chamber annulus36, there being a peripheral packing member 31 therebetween so that theflange 34 will serve to hermetically close the large end of the housingannulus '38 and support the rotor 28 in a position complemental to theinterior of the housing It to co-operate therewith so as to rotaterelative thereto with the passage of the liquid 33 from the receptaclell therebetween for discharge to the treatment housing annulus 36.

A comparatively coarse screen 33 fltted to a frame 40 is supported bythe peripheral edge ll of the receptacle l8. Cream or similar dairyproducts is taken directly from the pasteurizer or storage where it mayhave been retained to effect preserved freshness under reducedtemperatures, and then directed to the receptacle I! for initialstraining through the wire screen 33 or directly supplied to the entrantorifices of the conduit coupler 20 from storage or the pasteurizer. Thesubstance then flows down the conduit 11 for subjection to a physicalpressure reaction which elevates the temperature thereof for mechanicaldispersion of the fat globules with incident emulsification and/orpasteurization depending upon the extent of the pressure and degree ofconstriction. In the present embodiment heat of pasteurization may bedeveloped mechanically incident to the passage of the substance througha constriction or between surfaces in frictional reaction through themedium of the liquid flowing therebetween to eflect pasteurization, ifdesired, during the movement thereof along a predetermined path. This isaccomplished by passing successive increments of the substance in aliquid condition' through a constriction of any type where heat will beevolved as a consequence thereof, but primarily to reduce the fatglobules to minute particles solid which are of less magnitude than theforeign substance therein contained.

In order to efl'ect the traverse of the liquid through a constrictionfor breaking down the fat globules and, if desired, creating heat ofpasteurization incident to the traverse thereof, the cream or otherdairy product flows under the influence of gravity to the conduit 23which communicates with the apex of the conical rotor 88 splined orotherwise fixed to the shaft extremity 29 for rotation therewith inproximity to the correspondingly shaped interior surface 42 of thetreatment housing l4, thereby defining a minute constrictiontherebetween for the passage of the edible liquid from the receptaclel8. The conical rotor 28 has helical convolutions in the form of spiralgrooves 43 proximate to the apex thereof to enable or institute thetravel of the substance between the confronting surfaces 42 and 44 ofthe treatment housing l6 and rotor 28, respectively, which are inpressure reaction through the medium of the liquid traversingtherebetween. The extent of the constriction defined between thesurfaces 42 and 44 may be modified to conform with the desired treatmentor required heat of pasteurization through the medium of a knurled wheelwhich is fixed to the sleeve 21 to effect the rotation thereof relativeto the shaft 28 and bearing l5 which is in threaded engagementtherewith, thereby effecting slight reciprocable movement of thetreatment housing l6 axially in the direction of or from the rotor 28.To this end, a pointer 46 is fixed to the adjust ing knob 45 formovement therewith and relative to a graduated plate 41 to indicate theadjustment or extent of the constriction between the confrontingsurfaces 42 and 44 which is a factor of the housing l6 relative to therotor 28. The packing 31 permits the relative movement between thetreatment housing annulus 36 and its closure member 34 constituting apart of the shaft bearing 33.

Rotation of the shaft 38 will effect the traverse of the liquid alongthe constriction 4244. Gradually the liquid will build up and densifytherealong owing to the progressive lessening depth in the convolutiongrooves 43 until reaching the smooth or uninterrupted periphery 44 ofthe rotor 28 for further displacement and substantially increasedcompression and pressure deformation resulting in the dispersion of thefat globules about the conically arcuate surface thereof to cooperatewith the correspondingly shaped surface 42 of the treatment housing 6.As shown,

the treatment housing I6 terminates in the enlarged annulus 36 defininga peripheral chamber 48 for the reception of the treated liquid from theconstriction 4244. The liquid is thus subjected .9 to a pressurereaction which in conjunction with the frictional contact of therelatively moving surfaces 4244 therewith, elevates the temperature ofthe moving substances to a point of pasteurization, or, if desired,merely sufficient to aid in mechanical dispersion of the fat globulesconstituting' the primary constituent thereof. Fat globule dispersioninto minute particles is primarily sought so as to separate such fromthe foreign matter for eventual removal as will more clearly appearhereinafter.

The degree of temperature elevation and the maintenance thereof at apredetermined magnitude as well as the extent of dispersion may becontrolled by the distance of the rotor surface 44 with respect to theinterior surface 42 of the housing l6 responsive to adjusting ormanipulating the manually operated knob 45 as conditions may require ordeem advisable. During this passage of the liquid 88, heat ofpasteurization may be, if desired, developed incidental to the rotationof the rotor surface 44 which also serves to effect movement thereof toits periphery for discharge into the chamber 48 to impart improvedtexture, uniformity and the desired consistency thereto. It is thusapparent that the use of extraneous heat such as steam or any othervapor or heat medium is entirely avoided, and the treatment effected ina manner which imparts complete homogeneity to the resulting productwithout any possible disintegration or separation of the elements ortheir composition with the result that the fat globules are finelydivided to pass through exceedinglyflne strainers so as to extract theforeign matter therefrom.

Discharge of the liquid from the constriction and thence the strainingthereof is effected primarily by the centrifugal urge imparted theretoand effective thereon at the periphery responsive to the rotation of therotor-28. The temperature of the liquid 38 in the receptacle I8 isregistered by a thermometer 48. The consequent increase in temperatureresponsive to the passage through the treatment housing 6 is determinedfrom another thermometer 50 which is located in the discharge pipe 5| incommunication with the interior 48 of the housing annulus 36.

The extent of fat globule dispersion and the degree of pressuresubjection can be relatively determined from a pressure gauge 52 whichis mounted for communication with the interior of the treatment housingl6. The treated liquid is then conveyed to a non-pressure strainermechanism to be described hereinafter, for the purpose of removing allforeign matter without interfering with continuous treatment describedsupra. With the indicators described thus far, it will be apparent thatuniform regulation is rendered possible through the instant selectedadjustment of the various instrumentalities for temperature and pressuremaintenance within the required range for procuring the best results.

In order to remove all foreign matter from the treated liquid, thedischarge conduit 5| communicates with a pipe 53 comprising a part of avertical cylindrical pipe housing 54 that is supported by a bracket 55.The bracket 55 is, in this instance, an extension of the frame l2,thereby effecting the rigid support of the cylindrical housing 54, whichhas a depending extension 56. The extension 56 has a frusto-conicalperiphery 51 to serve as a vertical and bearing for a liquid distributorhousing 58 having radially extending tubular members 59, in thisinstance three, for rotary support by an axial bearing 68 correspondingin shape and size to serve as a complement for the depending extension56 of the cylindrical pipe housing 54. The pipe housing 54 has an axialtubular rod bearing and sleeve 6| for journalled support of a rod 62which is held in position by an end collar 63 resting upon the pipehousing end 64.

The rod bearing and sleeve 6| has an exteriorly threaded enlargement 65for axial engagement with the bearing extension 56, thereby maintainingsuch in assembled position with the rotary rod 62 extending therethroughto carry a bracket 66 to which leather straps 61 are radially attachedfor rotary slapping application to the walls of cylindrical straininghousings 68, in

" istry with a pair of cylindrical strainers 12 and .13, respectively.

The cylindrical strainers 12 and 13 are maintained rigid by means ofcircular end rings 14-15 and 18-11 which are concentrically sized indiameter to correspond with the grooves 10 and 1|, respectively, andthese are maintained in rigid spaced relation by rods 18 and 19 whichbridge the ring members 14-15 and 16-11, respectively, so as to define aframework for the strainer walls 80 and 8| and their respective strainerbottoms 82 and-83, thereby defining the cylindrical strainers 12 and 13,respectively. These strainers 12 and 13 are preferably though notnecessarily of Monel metal construction with and two-hundred and fifty(250) fifty (50) I meshes to the inch respectively. There is no externalpressure exerted upon the liquid flowing through these strainers.Gravity alone is relied upon to effect liquid passage through thestrainers which are, in effect, non-pressure liquid cleansingexpedients.

Many different expedients could be utilized in sustaining the strainers12 and 13 in concentric relation with their housing 68, and in thepresent embodiment it is accomplished by means of substantially U-shapedbrackets 84 pivoted to each plate member 69 as at 85 and 86 to carry athumb stud 81 through the bottom thereof. The thumb studs 81 co-operatewith a'bottom bracket 88 comprising cross-members or straps 90 and SIhaving upturned extremities 92 for reception of the strainer housing 68thereon and concentrically with the strainers 12 and 13 which are inregistry with the grooves 10 and H provided in the plate members 69 andthus held in detachable spaced relation through the adjustability of thethumb stud 81.

Another type of bottom bracket is shown in Figures 8 and 9, itcomprising a plate 90 having concentric grooves 10 and H to confront thegrooves 10 and 1| in the distributor plates 53. Radially extending ears8|, in this instance four, terminate in upturned extremities 92' forreception of the strainer housing 68 thereon and concentrically with thestrainers 12 and 13 for support by the U-shaped bracket 84 or any otherexpedient to accomplish that purpose. The strainer housings 68 andcylindrical strainers 12 and 13 are thus rendered detachable forcleansing and sterilizing purposes as will appear more fullyhereinafter.

Now, then, the vertical bearing 54 is tubular to define a communicatingpassage 83 with the conduit 53 to effect or enable the flow of thetreated cream or other liquid to the radial distributor member 58 havingtheir tubular interior' 84 in communication therewith. The distributors58 are thus in communication and establish a passage with the interiorof the strainer housings 68 through the axial ports 95 in thedistributor plates 68. 'Flow of the treated liquid is maintained withonly one housing 68 at a time, since the tubular bearing extension 56has a single transverse port 96 which is capable of registry with onlyone distributor member 58.

To insure correct registry of one distributor 58 for rotary displacementto effect successive registry as desired, a spring impelled detent 81having an enveloping spring 88 is confined in a housing 89 forattachment to the frame bracketii 55. A lever I is connected to thedetent 91"5 above its housing 88 to enable the vertically up--' warddisplacement thereof against the urge of the spring 88, thereby removingthe pin or detent 91 from an aperture or concavity IOI provided in thetop surface of each distributor 58.

Consequently, successive registry is established and the treated liquidflows through the strainer housings 68 for removal of the foreign mattertherefrom.

' The passage of the treated liquid through the strainers 12 and 13 isassisted by a slight vibratory movement imparted to the strainerhousings 68 by the rotating slapping straps 61 which are driven by theshaft 62 having a pulley I02 carries a belt I03 which is in peripheralcontact with a smaller pulley I04 fixed to the armature shaft I05 of amotor I06. The motor I08 has a bracket I01 to enable the attachment tothe frame I2 which has an enclosing housing I01 for the motor I05."Similarly, the drive shaft 30 of the rotor 28 terminates in a couplerI08 which enables the connection thereof to an armature shaft I08 of alarge motor IIO mounted on the frame I2 for enclosure by the housing I2which in part supports the receptacle I8 through the brackets I9.

The motors I08 and H0 may be controlled from a single switch orotherwise as commercial practice may dictate. A pressure gauge III ispreferably provided in the vertical bearing 54,

communication with the interior passage 83 thereto to determine thepressure of the flow as the emulsifying treatment is ended. Then, too, aspigot H2 is preferably provided for attachment to the vertical bearing54 so as to eflect communication with the interior passage 83 thereof toallow a sample of the liquid to be removed at any time for test andobservation purposes. It will thus be apparent that a very novel methodof treating liquids, such as cream and 4,5

similar dairy products, has been provided so as to break down the fatglobules into minute particles and thus allow their passage through veryfine strainers 12 and 13, with all foreign substance retained therein toeffect the continuous puri- 5o pipe II3 having communication with aclosure member II4, which may serve as the top of a strainer housing 68,together with its cylindrical strainers 12 and 13 confined therein. Tothis end the closure I I4 is provided with a handle I I5 to enable themanipulation thereof and. the in- 55 terior of the closure I I4 has aplate I I6 with concentric grooves II1 and 8 which resemble inappearance and structure the plate member shown in Figure 8. Inconsequence thereof the strainers 12 and 13 will be held in the desiredspaced relation in conjunction with a bottom plate member H8 constructedsimilarly to plate member II6 to enable the removal of all foreignmatter from the strainers 12 and 13 as well as the interior of thestrainer housing 68 for pas 15 sage to a funnel shaped bottom I20 havingcommunication with a pipe I2I for refuse. Any suitable clamp members I22and I23 may be provided in connection with the top closure I I4 forgrasping lugs I24 provided on a circular band I25 which is sectional instructure for detachable mounting to the strainer housing 68. A bracketI25 is provided to support the entire structure in any suitable mannerso as to provide cleaning means that enable the ready and speedyattachment and detachment of the cylindrical strainers I2 and I3together with their housing 68. For that matter the cleaning devicedescribed above may have its own housing whereon the lugs I24 arepermanently attached and thus merely cleanse the strainers I2 and 13 bysubjection to steam, while the regular housing 68 may be washed orotherwise rendered sanitary as commercial practice may dictate.

In the modified embodiment shown in Figures 12 and 13, the treatmenthousing I6 with its auxiliary instrumentalities are entirely dispensedwith and the fluid or dairy liquid is passed directly from thereceptacle I8 to a strainer housing 68' and its interiorly confinedcylindrical strainers I2 and I3. This is effected by means of a conduit20 establishing connection with a nipple I26 which is in threadedengagement with the top plate 69, having the features described inconnection with the distributor plate 69 in the preferred embodiment.The bracket clamp 84' with its adjustable thumb 81' retains the cleaninghousing 68 with its interior strainers I2 and I3 in position. A slappingmechanism is supported by a bracket 60 having vertically aligned bearing6| for supporting a rod or shaft 62' with leather strap members 61attached thereto for contact with the wall of the housing 68' to impartthe desired vibratory movement thereto.

As shown, a pulley I02 is aifixed to the top extremity of the shaft 62to carry a belt I03 around the periphery of a small pulley I04 fixed tothe armature shaft I05 of a motor I06. The motor I06 has a bracket I 01'for attachment to the frame bracket 60', thereby imparting the desiredvibratory movement to the strainer housing 68' so that the liquid willfiow therefrom with the foreign matter removed by the strainers I2 and13. A receptacle such as a milk can I21 may be placed below the strainerhousing 68' so as to receive the strained liquid in the funnel shapedmember I28 which is supported within the receptacle I21 to avoid foamingof the liquid which fiows therethrough.

With this arrangement of parts, it will be apparent that a novelnon-pressure straining mechanism of exceedingly high efiiciency has beenprovided to remove the vast amount of foreign matter that is inherent incream and other dairy substances upon arrival at the creameries forchurning into butter or other dairy products. The treatments of theliquids are described in connection with the structural embodiment ofthe invention disclosed in Figures 1, 2 and 4 also aids in reducing therequired time of churning in the production of butter and other dairyproducts. This coupled with the purity of the product and its improvedtexture, taste, color and keeping qualities renders such highlydesirable over ordinary cream and similar dairy products that are notsubjected to the purification treatment herein described.

It should be noted that vitamin D may be imparted to the cream beforecharging the receptacle I8 therewith. Also, cloth strainers may, if

desired, be substituted for the metal strainers I2-I3 or I2I3 shouldcommercial practices so dictate. It is significant, too, that thepassage of the substance through the constriction defined by therelatively moving surfaces 42-44, produces a galvanic plastic actionwhich. prolongs the keeping qualities thereof and aids in thepurification thereof in conjunction with the straining effect requiredby the subsequent passage therethrough.

Various changes may be made in the embodiments of the invention hereinspecifically described Without departing from or sacrificing any of theadvantages thereof within the scope of the appended claims.

We claim:

1. A filter unit comprising in combination a series of verticalcylindrical filter chambers 10- driving said slapping devices with arotary movement on the centrally vertical axis as aforesaidsubstantially as described.

2. A method of treating milk and other lactic products containing fatglobules for the purpose of homogenizing and purifying the same, whichconsists in first subjecting said material to a vigorous homogenizingaction for the purpose of homogenizing said material and simultaneouslyraise its temperature under control due to said action, to therebyimprove the condition of the fatty globules for subsequent filteringoperation, and which treatment consists in immediately thereaftersubjecting such material to a filtering action while at the increasedtemperature occasioned by said first treatment, substantially asdescribed.

3. A method of treating milk and other lactic products containing fattyglobules for the purpose of homogenizing the same and removing foreignmatter therefrom which consists in first subjecting said material to avigorous homogenizing action to thereby homogenize such material andraise the temperature thereof under control to a degree selected forplacing the fatty globules in improved condition for subsequenttreatment, and which consists in immediately thereafter and at saidincreased temperature subjecting said material to treatment in amechanical filtering device for the mechanical removal of foreignimpurities therefrom substantially as described.

4. A filter unit comprising in combination a series of vertical filterchambers having within them suitable filtering devices, inlet passagesat the upper ends of said chambers, delivery passages at the lower endof the chambers, a central supply passage in close proximity to theupper inlet passages and having a single liquid supply connectiontogether with means for advancing the filter units about the centrallyvertical axis as a group to thereby successively place the inletconnections of the filter elements in communication with the supplypassage substantially as described.

CHARLES DOERING. HENRY DOERING.

